Some times applications need to execute tasks that may take a long time to finish.
Ideally the users should be able to keep track of the progress of the tasks being executed, so they know how much of the whole task has been done and what long it may take to end.
This class can help solving these problems using AJAX requests to trigger the execution of long one or more tasks on the server side, as well retrieving information about the progress of the tasks while they have not yet finished.